MAUDE Adverse Event Report: SIEMENS HEALTHCARE DIAGNOSTICS, INC. ADVIA CENTAUR XPT TOXOPLASMA G (TOXO G); TOXOPLASMA GONDII IMMUNOASSAY

Model Number N/A

Device Problem False Positive Result (1227)

Patient Problem No Known Impact Or Consequence To Patient (2692)

Event Date 06/25/2020

Event Type  malfunction  

Manufacturer Narrative

Siemens healthcare diagnostics is investigating.Siemens retrieved siemens remote services (srs) advia centaur xp/xpt qc data for qc lot 612060 and toxo g lots 250, 253, 259 and 261.Lot 261 is recovering similarly with lots 250 and 253 and qc is well within insert ranges.Lot 250-mean/sd: 6120601, 1.371/ 0.49, lot 253-mean/sd: 1.426/ 0.26, lot 259-mean/sd: 0.828/ 0.23, lot 261-mean/sd: 1.417/ 0.67; 6120602, 29.623/ 1.67, 32.46/ 1.7, 25.503/ 1.58, 23.458/ 1.28.Siemens retrieved srs advia centaur xp/xpt patient data from (b)(6) 2019 - (b)(6) 2020 and this is the summary of all toxo g lots.The rate of result interpretations for reagent lot 261 recover similar and comparable with the other reagent lots reviewed.Lot 246: lot 248: lot 250: lot 253: lot 259: lot 261: negative: 4763 (78.44%), 1911 (76.62%), 3561 (77.6%), 1603 (75.0%), 2286 (76.9%), 1521 (81.6%).Equivocal: 79 (1.3%), 37 (1.48%), 46 (1.0%), 45 (2.1%), 38 (1.3%), 18 (1.0%).Positive: 1230 (20.25%), 546 (21.89%), 984 (21.4%), 488 (22.8%), 646, (21.8%), 324 (17.4%).Total : 6072, 2494, 4591, 2136, 2970, 1863.The advia centaur xp/xpt toxo g instructions for use states in the limitations section: "human anti-mouse antibodies (hama) or heterophile antibodies may be present in samples from individuals exposed to mouse or animal immunoglobulins from natural sources or as part of disease therapies.These antibodies may interfere with the advia centaur toxo g assay and give falsely positive or falsely negative results.These samples should not be tested." "the presence of anti-nuclear antibodies (ana) and anti-mitochondrial antibodies (ama) in samples from patients with autoimmune syndrome may interfere with the advia centaur toxo g assay and give falsely positive or falsely negative results.These samples should not be tested." mdr 1219913-2020-00177 was filed for the (b)(6) 2020 results.Mdr 1219913-2020-00178 was filed for the (b)(6) 2020 result.

Event Description

Discordant (false positive) results were obtained on four samples from one patient using advia centaur xpt toxoplasma g (toxo g) lot 261.The customer tested a sample on (b)(6) 2020 and obtained a positive result, which was reported to the physician.It is unknown if the physician questioned the result.Historical toxo g results for this patient were negative, so on (b)(6) 2020, the customer retested the sample and also the two stored samples that were used to obtain the negative historical results (lot number used for the historical results is unknown).Positive results were obtained on the three samples using advia centaur xpt toxo g lot 261 on (b)(6) 2020.The customer also tested these three samples using an alternate method and negative results were obtained.A new sample was drawn from the same patient and tested using advia centaur xpt toxo g lot 261.A positive result was obtained, but a negative result was obtained on an alternate method.There are no known reports of patient intervention or adverse health consequences due to the false positive advia centaur xpt toxo g results.

Manufacturer Narrative

Siemens healthcare diagnostics filed initial mdr 1219913-2020-00176 on 07/22/2020.Additional information from 10/09/2020: siemens completed an internal study on atellica im system for toxoplasma igg (toxo g) assay.During the study toxo g reagent lots 258, 260 and 262 were used.Toxo g reagent lot 252 expired on (b)(6) 2020 and was relabeled to reagent lot 997.Results generated with lot 997 were solely for informational purposes.Atellica im toxo g lot 252 is the same bulk material as advia centaur xpt lot 253, atellica im toxo g lot 258 is the same bulk material as advia centaur xpt lot 259, atellica im toxo g lot 260 is the same bulk material as advia centaur xpt lot 261 and aim toxo g lot 262 is the same bulk material as advia centaur xpt lot 263.The reagent components are the same, hence a similar trend in the study results is expected to be produced with advia centaur xpt lots.Fifty (50) normal patient samples from siemens and fifty (50) patient samples acquired via vendor in france were tested in replicates of 3 (n=3).The final interpretation was the same for all 50 samples from france and for 49/50 patient samples from siemens.The one siemens normal patient sample was reactive with reagent lots 997, 258 and 260 and equivocal with reagent lot 262.This is a cut off sample (10.0 iu/ml) and recovery was within acceptable precision at that level.Siemens continues to investigate.Mdr 1219913-2020-00177 supplemental 1 report was filed for the same event (06/29/2020 results).Mdr 1219913-2020-00178 supplemental 1 report was filed for the same event (07/01/2020 result).

Manufacturer Narrative

Siemens healthcare diagnostics filed initial mdr 1219913-2020-00176 on 07/22/2020 and mdr 1219913-2020-00176 supplemental 1 report on 11/04/2020.Additional information - 12/07/2020.Siemens has concluded the investigation for a false reactive result on different samples from the same patient using advia centaur xpt toxoplasma igg (toxo g) lot 261.A patient with historically non-reactive toxo g results recovered reactive with advia centaur xpt toxo g lot 261.The sample was retested along with the stored (historical) samples for this patient using advia centaur xpt toxo g lot 261 and an alternate method.All results with the alternate method recovered as nonreactive.Heterophilic blocking tube (hbt) results were not provided.Customer's calibration data was reviewed and was comparable to internal lot release data.Customer's quality control data recovered within acceptable range.Advia centaur xpt toxo g siemens analytics service (sas) patient data from (b)(6) 2019 to (b)(6) 2020, that included txog lots 246-261, recovered similarly for interpretation rates with the previous lots.Siemens initiated an internal study that included atellica im (aim) toxo g lots 252, 258, 260 and 262, fifty (50) normal patient samples from manufacturing and fifty (50) patient samples from france (an approved siemens supplier and french acquisition company (inospecimens niobank)).Aim toxo g lot 252 is the same as advia centaur xpt lot 253, aim lot 258 is the same as advia centaur xpt lot 259, aim lot 260 is the same as advia centaur xpt lot 261 and aim lot 262 is the same as advia centaur xpt lot 263.The reagent components are the same, hence a similar trend in the study results is expected to be produced with advia centaur xpt lots.All samples were tested in replicates of 3 (n=3).The final interpretation was the same for all patient samples across all reagent lots, with the exception of 1 sample from siemens.That sample was near the cutoff of 10 iu/ml and recovery was within acceptable precision at that level.The total number of negative samples the customer has tested with advia centaur xpt lot 261 was not provided therefore, specificity cannot be calculated.Based on the investigation results, a product performance issue has not been identified.No further evaluation of the device is required.The type of investigation, investigation findings and conclusion codes have been updated to reflect the investigation results.Reference section h6 of this report for the final codes for this event.Mdr 1219913-2020-00177 supplemental 2 report was filed for the same event (06/29/2020 results).Mdr 1219913-2020-00178 supplemental 2 report was filed for the same event (07/01/2020 result).

• Brand Name: ADVIA CENTAUR XPT TOXOPLASMA G (TOXO G)
• Type of Device: TOXOPLASMA GONDII IMMUNOASSAY
• Manufacturer (Section D): SIEMENS HEALTHCARE DIAGNOSTICS, INC.; 511 benedict avenue; tarrytown, ny
• MDR Report Key: 10311547
• MDR Text Key: 242159859
• Report Number: 1219913-2020-00176
• Device Sequence Number: 1
• Product Code: LGD
• UDI-Device Identifier: 00630414208459
• UDI-Public: 00630414208459
• Combination Product (y/n): N
• PMA/PMN Number: K102681
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: foreign,health professional,u
• Type of Report: Initial,Followup,Followup
• Report Date: 01/04/2021

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Expiration Date: 02/14/2021
• Device Model Number: N/A
• Device Catalogue Number: 10310321
• Device Lot Number: 261
• Was Device Available for Evaluation?: No
• Initial Date Manufacturer Received: 06/29/2020
• Initial Date FDA Received: 07/22/2020
• Supplement Dates Manufacturer Received: 10/09/2020; 12/07/2020
• Supplement Dates FDA Received: 11/03/2020; 01/04/2021
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1
• Patient Age: 22 YR